Compartment bag assembly for dispensing containers

ABSTRACT

A product dispensing container of the type including a collapsible product containing a bag assembly which is disposed within a rigid container and defines a chamber therein. The chamber is filled with a propellant. A valve dispensing means communicates with the bag assembly for discharging the product therefrom under the force of the propellant. The product containing bag assembly includes a compartment bag constructed so as to be only axially collapsible when subjected to the radial and axial forces of the propellant. The bag assembly further includes a barrier bag or sheath which encloses the compartment bag. The barrier bag is made from an impermeable film material and is flexible so as not to influence the axial collapse of the compartment bag.

United States Patent 1191 Borchert 1 51 Aug. 13, 1974 COMPARTMENT BAGASSEMBLY FOR DISPENSING CONTAINERS [75] Inventor: Jerome A. Borchert,Glenwood, Ill.

[73] Assignee: Continental Can Company, Inc.,

New York, NY.

Primary ExaminerRobert B. Reeves Assistant ExuminerFrancis J. BartuskaAttorney, Agent, or Firm-John J. Kowalik; Joseph E. Kerwin; William A.Dittmann [57] ABSTRACT A product dispensing container of the typeincluding a collapsible product containing a bag assembly which isdisposed within a rigid container and defines a chamber therein. Thechamber is filled with a propellant. A valve dispensing meanscommunicates with the bag assembly for discharging the product therefromunder the force of the propellant. The product containing bag assemblyincludes a compartment bag constructed so as to be only axiallycollapsible when subjected to the radial and axial forces of thepropellant. The bag assembly further includes a barrier bag or sheathwhich encloses the compartment bag. The barrier bag is made from animpermeable film material and is flexible so as not to influence theaxial collapse of the compartment bag.

5 Claims, 3 Drawing Figures PATENIED AUG 1 31974 x "MIIIIIIIIISIL JCOMPARTMENT BAG ASSEMBLY FOR DISPENSING CONTAINERS BACKGROUND ANDSUMMARY OF THE INVENTION The present invention relates to productdispensing containers which include a product containing compartment anda propellant compartment. The compartments are generally separated by acommon wall of the product containing compartment. In some instances,the common wall of such dispensing containers is defined by acollapsible bag positioned internally of the container body and securedto a top closure of the latter. The top closure generally includes amanually operable valve-actuated dispensing mechanism for dispensing aproduct packaged within the bag under the influence of a pressurizedpropellant housed in the propellant chamber between the bag and thecontainer body.

One form of collapsible bag includes fold bands axially spaced from eachother to provide a pleat-like wall for rigidifying the bag andmaintaining its shape against the forces acting radially and axiallythereon so that the bag collapses uniformly both radially and axiallywithout the panelling or indiscriminate folding. The elimination of theindiscriminate folding prevents blockage to the dispensing valve.

The collapsible bags are made from a plastic material such aspolyethylene or the like and formed by molding such as blow molding.However, unless special precautions are taken these bags have problemswith gas permeation of the propellant into the bag which may result inan undesirable mixture of the bag contents and the propellant. For thisreason, the material from which the bag is made has been restricted toplastic compositions having special formulations which tends to minimizethe permeation. These special formations have increased the the cost ofthe bag while not always providing the necessary impermeability.

By the present invention, it is proposed to provide a compartment bagarrangement which overcomes the permeability of propellant gas into theproduct containing or compartment bag.

This is accomplished by a compartment bag arrangement comprising acollapsible bag having a generally pleated structure to resist theradial and axial pressure forces exerted by the propellant so as toeliminate panelling or indiscriminate folding in a manner causingblockage of the product. The bag is retained in a container bodyclinching the open end of the bag between the rolled rim at the upperopen end of the container body and the dome in which the dispensingvalve is mounted.

Disposed about the pleated compartment bag is a barrier sheath or bagwhich is also clinched between the rolled edge and the dome. The barriersheath is of a laminated flexible structure of which of least one of thelayers is flexible non-permeable material.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a longitudinal crosssectional view of the dispensing container with parts broken away forclarity, and showing a bag arrangement embodying the structure of theprevent invention.

FIG. 2 is a longitudinal section view of the dispensing container ofFIG. 1 with parts broken away for clarity and illustrating a partiallycollapsed position of the bag arrangement.

FIG. 3 is a greatly enlarged fragmentary sectional view of the encircledportion of FIG. 1 and showing in particular the manner in which the bagarrangement is secured to the container.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2,there is shown a product dispensing container I0 of the general typewith which the product dispensing bag assembly 11 of the presentinvention is adapted to be used. The container 10' comprises generally acontainer body 12 in which a product dispensing bag assembly 11 carriesthe product to be dispensed, and a propellant chamber 13 defined betweenthe exterior of the bag assembly 11 and the inside wall of the containerbody 12.

The container body 12 includes axially opposed top and bottom closures14 and 16, respectively. The top closure 14 comprises a dome 17 formedwith an axial opening 18 bounded by a rolled rim 19. The product isfilled through the opening 20 into the product dispensing bag assembly11. After the bag assembly 11 is filled, a cup 21 supporting adispensing valve 22 which may be of well-known construction is attachedto the rim by clinching. The bottom closure 16 is formed with an opening23 in which a grommet or charging valve 24 is seated, The propellant ischarged into the propellant chamber 13 through the charging valve in anyone of the well-known procedures.

The compartment bag assembly 11 includes a collapsible product bag 26and an outer sheath or protective bag 27. The collapsible product bag 26is formed from a plastic material such as polyethylene and preferably byblow molding. The bag 26 is sufficiently thick so as to be capable ofretaining its configuration under normal atmospheric pressure and underthe propellant pressure forces acting thereon when the bag is completelyfilled with a product. The collapsible bag 26 includes a cylindricalside wall 28, a bottom wall or base 29 located in vertically spacedrelationship with respect to an upper domed end portion 31. The upperdomed end portion 31 of the bag is open and is fastened to the rim asmore fully to be explained hereinafter.

To regulate the collapsing of the product bag 26 in a manner toeliminate indiscriminate panelling of the cylindrical wall 28 and thebottom wall 29, there is provided a plurality of lengthwise spaced foldsections 32. As shown, the fold sections 32 are spaced lengthwise of thecylindrical wall 28 so as to define therebetween a plurality of annularside bands 33. The fold sections 32 each comprise a pair of annularpanels 34 which are arranged in V-shaped configuration and integrallyjoined along a common inner fold line defining the vortex of the V. Theouter ends of the annular panels 3434 are integrally joined along foldlines to the upper and lower edges of the adjacent annular bands 33.Preferably the fold panels 3434 are inclined inwardly at about an angleof 60 relative to the annular bands 33. For a more detailed descriptionof the structure of the product bag 26, reference is made to US. Pat.No. 3,467,283.

The outer barrier sheath or protective bag 27 is of generally tubularconstruction and includes a side wall 36 and a bottom wall 37 and anopen upper end 38. The sheath 27 is sized to loosely encompass thecompartment bag 26 and is made from a non-permeable film material toprovide a gas barrier between the propellant and the interior of thecompartment bag 26. In the embodiment shown, the impermeable film is ofa laminate or co-extruded structure of polyethylene. An imperviousplastic material such as Saran polyethylene I and a metal foil laminatestructure of polypropylene and polyester plastic may also be used toform a protective barrier. The wall of the sheath 27 is of minimumthickness so that it collapses indiscriminately and in this way does notinterfere with the controlled collapse of the compartment or product bag26.

The compartment bag 26 is inserted into the straight sided and flexibleprotective sheath 27 and the upper end thereof is fastened to thecollapsible compartment bag 26. This may be accomplished by insertingthe loosely assembled barrier bag 27 and compartment bag 26 through theopening 18 in the dome 17. A heat flanging tool is then inserted intothe bag opening and into engagement with the upper ends of the sheath 27and the compartment bag 26 so that they are simultaneously sealed toeach other and over the curl 19. Thereafter, the cup 21 is seated in theopening and clinched over the prior heat sealed area of the compartmentbag 26 and the sheath 27 and the curl 19. Alter natively, thecompartment bag 26 may be loosely inserted into the sheath 27 prior toinsertion of the latter into the can body 12. The sheath 27 may then beheat sealed to the internal compartment bag 26 at the dome area whichnormally overlies the curl. The assembled sheath 27 and the compartmentbag 26 may then be inserted into the can body in the more or lessconventional manner with the sealed area on the curl 19. The cup 17 isthen clinched over the curl 19 thereby clamping the bag assembly 11therebetween.

In operation when the valve 22 is released so that the product isdispensed therethrough, the pressure forces of the propellant within thepropellant chamber 13 are operative to react on bag assembly 11 to forcethe compartment bag 26 axially upward. As the bag 26 moves axiallyupward, the annular panels 34-34 each fold about the inner fold line andthe outer fold lines. As the panels 3434 fold during dispensing of theproduct, the included angle therebetween gradually decreases until thepanels lie in superimposed horizontal relationship. The panels 34-34thus form in the nature of rigidifying bands which resist the radialforces acting on the side wall 29 to prevent radial collapse of thebands 33 inwardly. At the same time, the panels 34-34 also exert anaxial force tending to maintain the base 24 substantially normal to theside wall of the container body 12 whereby the bag collapses uniformlyalong its length without tilting relative to the longitudinal axis. Inthis manner the contraction of the product dispensing bag 26 isregulated and controlled. At the same time, the barrier bag or sheath27, which is flexible, is indiscriminately forced against the sides ofthe compartment bag 26. The sheath 27 does not, because of itsflexibility, influences the discharge of the product from the bag 26.

As the product is further dispensed through the valve 22 after thepanels 34-34 are folded superimposed relationship, the side bands 33collapse irregularly under the force exerted by the propellant. As shownin FIG. 2, the side bands collapse by folding so that substantiallyareas of the outer surfaces thereof are in face to face contact. In thisconnection, it should be mentioned that the width of the side bands 33is preferable such that in the collapsed condition, no portion thereofis disposed outboard of the vortex of the collapsed panels 34-34 therebyto provide an uninterrupted center passage for the flow of the productto the dispensing valve 22. Moreover, the thickness of the collapsedside ban ds 33 is substantially uniform about the circumference so thata minimum of axial tilting occurs whereby the base 29 remainssubstantially parallel to the bottom closure 14 when the compartment bag26 approaches the dome 17. The base 29 may bulge upwardly to forcefurther product through the valve 22. During the entire collapse of thecompartment bag 26, the barrier bag 27 is held by the pressure forces inindiscriminate engagement with the bag 26. The barrier bag 27 is of thinwall construction in the nature of a film and provides a barrier layerwhich serves to prevent permeation and mixture of the propellant withthe contents of the compartment bag 26.

What is claimed is:

1. In a product dispensing container having a pressurized container bodyincluding a base and a top closure at axially opposite ends of saidbody, a dispensing valve carried by said top closure, and a collapsibleproduct dispensing bag assembly disposed in the interior of saidcontainer body and defining with said container body a propellantchamber charged with a pressurized propellant, said bag assemblycomprising a productcontaining compartment bag having a plurality oflengthwise spaced fold sections so as to be axially collapsible, and anon-dispensing closed gas filled tubular sheath attached to andenclosing said compartment bag for transmitting pressure from thepropellant chamber to the compartment bag, said tubular sheath beingmade from an impermeable film to provide a barrier between saidcompartment bag and said propellant chamber and maintaining the initialquantity of gas therein during the entire operating period, to maximizedispensing of the product contained in said bag assembly.

2. The invention as defined in claim 1 wherein said tubular sheath isattached to the upper end of said compartment bag.

3. The invention as defined in claim 2 wherein said tubular sheath isattached to said compartment bag by a heat seal.

4. The invention as defined in claim 3 wherein said compartment bag ismade from plastic, and wherein said tubular sheath is made from alaminate having at least one layer of plastic.

5. The invention as defined in claim 4 wherein said laminate includes ametal foil layer.

1. In a product dispensing container having a pressurized container bodyincluding a base and a top closure at axially opposite ends of saidbody, a dispensing valve carried by said top closure, and a collapsibleproduct dispensing bag assembly disposed in the interior of saidcontainer body and defining with said container body a propellantchamber charged with a pressurized propellant, said bag assemblycomprising a productcontaining compartment bag having a plurality oflengthwise spaced fold sections so as to be axially collapsible, and anondispensing closed gas filled tubular sheath attached to and enclosingsaid compartment bag for transmitting pressure from the propellantchambers to the compartment bag, said tubular sheath being made from animpermeable film to provide a barrier between said compartment bag andsaid propellant chamber and maintaining the initial quantity of gastherein during the entire operating period, to maximize dispensing ofthe product contained in said bag assembly.
 2. The invention as definedin claim 1 wherein said tubular sheath is attached to the upper end ofsaid compartment bag.
 3. The invention as defined in claim 2 whereinsaid tubular sheath is attached to said compartment bag by a heat seal.4. The invention as defined in claim 3 wherein said compartment bag ismade from plastic, and wherein said tubular sheath is made from alaminate having at least one layer of plastic.
 5. The invention asdefined in claim 4 wherein said laminate includes a metal foil layer.